Geniohyoid muscle

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Geniohyoid muscle
Geniohyoid muscle.PNG
Anterior view. Geniohyoid muscle labeled at upper center left
Geniohyoideus.png
Extrinsic muscles of the tongue. Left side.
Details
Origin Inferior mental spine of mandible
Insertion Hyoid bone
Artery Branches of the lingual artery.
Nerve C1 via the hypoglossal nerve
Actions Carry hyoid bone and the tongue upward during deglutition
Identifiers
Latin musculus geniohyoideus
TA98 A04.2.03.007
TA2 2166
FMA 46325
Anatomical terms of muscle

The geniohyoid muscle is a narrow paired muscle situated superior to the medial border of the mylohyoid muscle. It is named for its passage from the chin ("genio-" is a standard prefix for "chin") [1] to the hyoid bone.

Contents

Structure

The geniohyoid is a paired short muscle that arises from the inferior mental spine, on the back of the mandibular symphysis, and runs backward and slightly downward, to be inserted into the anterior surface of the body of the hyoid bone. [2] :346 It lies in contact with its fellow of the opposite side. It thus belongs to the suprahyoid muscles. The muscle receives its blood supply from branches of the lingual artery. [3]

Innervation

The geniohyoid muscle is innervated by fibres from the first cervical spinal nerve travelling alongside the hypoglossal nerve. [2] [4] [5] Although the first three cervical nerves give rise to the ansa cervicalis, the geniohyoid muscle is said to be innervated by the first cervical nerve, as some of its efferent fibers do not contribute to ansa cervicalis.

Variations

It may be blended with the one on opposite side or double; slips to greater cornu of hyoid bone and genioglossus occur.

Function

The geniohyoid muscle brings the hyoid bone forward and upwards. [2] This dilates the upper airway, assisting respiration. [4] During the first act of deglutition, when the mass of food is being driven from the mouth into the pharynx, the hyoid bone, and with it the tongue, is carried upward and forward by the anterior bellies of the Digastrici, the Mylohyoidei, and Geniohyoidei. It also assists in depressing the mandible. [3]

History

The inclined position of the geniohyoid muscle has been contrasted to the horizontal position in neanderthals. [6]

Additional images

See also

Related Research Articles

<span class="mw-page-title-main">Neck</span> Part of the body on many vertebrates that connects the head with the torso

The neck is the part of the body on many vertebrates that connects the head with the torso. The neck supports the weight of the head and protects the nerves that carry sensory and motor information from the brain down to the rest of the body. In addition, the neck is highly flexible and allows the head to turn and flex in all directions. The structures of the human neck are anatomically grouped into four compartments: vertebral, visceral and two vascular compartments. Within these compartments, the neck houses the cervical vertebrae and cervical part of the spinal cord, upper parts of the respiratory and digestive tracts, endocrine glands, nerves, arteries and veins. Muscles of the neck are described separately from the compartments. They bound the neck triangles.

<span class="mw-page-title-main">Hyoid bone</span> Bone situated in the neck between the chin and the thyroid cartilage

The hyoid bone is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. At rest, it lies between the base of the mandible and the third cervical vertebra.

<span class="mw-page-title-main">Suprahyoid muscles</span>

The suprahyoid muscles are four muscles located above the hyoid bone in the neck. They are the digastric, stylohyoid, geniohyoid, and mylohyoid muscles. They are all pharyngeal muscles, with the exception of the geniohyoid muscle. The digastric is uniquely named for its two bellies. Its posterior belly rises from the mastoid process of the cranium and slopes downward and forward. The anterior belly arises from the digastric fossa on the inner surface of the mandibular body, which slopes downward and backward. The two bellies connect at the intermediate tendon. The intermediate tendon passes through a connective tissue loop attached to the hyoid bone. The mylohyoid muscles are thin, flat muscles that form a sling inferior to the tongue supporting the floor of the mouth. The geniohyoids are short, narrow muscles that contact each other in the midline. The stylohyoids are long, thin muscles that are nearly parallel with the posterior belly of the digastric muscle.

<span class="mw-page-title-main">Infrahyoid muscles</span> Group of muscles

The infrahyoid muscles, or strap muscles, are a group of four pairs of muscles in the anterior (frontal) part of the neck. The four infrahyoid muscles are the sternohyoid, sternothyroid, thyrohyoid and omohyoid muscles.

<span class="mw-page-title-main">Omohyoid muscle</span> Human neck muscle

The omohyoid muscle is a muscle in the neck. It is one of the infrahyoid muscles. It consists of two bellies separated by an intermediate tendon. Its inferior belly is attached to the scapula; its superior belly is attached to the hyoid bone. Its intermediate tendon is anchored to the clavicle and first rib by a fascial sling. The omohyoid is innervated by the ansa cervicalis of the cervical plexus. It acts to depress the hyoid bone.

<span class="mw-page-title-main">Cervical plexus</span> Network of nerves in the neck

The cervical plexus is a nerve plexus of the anterior rami of the first four cervical spinal nerves C1-C4. The cervical plexus provides motor innervation to some muscles of the neck, and the diaphragm; it provides sensory innervation to parts of the head, neck, and chest.

<span class="mw-page-title-main">Digastric muscle</span> Small muscle located under the jaw in mammals

The digastric muscle is a bilaterally paired suprahyoid muscle located under the jaw. Its posterior belly is attached to the mastoid notch of temporal bone, and its anterior belly is attached to the digastric fossa of mandible; the two bellies are united by an intermediate tendon which is held in a loop that attaches to the hyoid bone. The anterior belly is innervated via the mandibular nerve, and the posterior belly is innervated via the facial nerve. It may act to depress the mandible or elevate the hyoid bone.

<span class="mw-page-title-main">Mylohyoid muscle</span>

The mylohyoid muscle or diaphragma oris is a paired muscle of the neck. It runs from the mandible to the hyoid bone, forming the floor of the oral cavity of the mouth. It is named after its two attachments near the molar teeth. It forms the floor of the submental triangle. It elevates the hyoid bone and the tongue, important during swallowing and speaking.

<span class="mw-page-title-main">Stylohyoid muscle</span> Muscle

The stylohyoid muscle is one of the suprahyoid muscles. Its originates from the styloid process of the temporal bone; it inserts onto hyoid bone. It is innervated by a branch of the facial nerve. It acts draw the hyoid bone upwards and backwards.

<span class="mw-page-title-main">Ansa cervicalis</span> From cervical plexus

The ansa cervicalis is a loop formed by muscular branches of the cervical plexus formed by branches of cervical spinal nerves C1-C3. The ansa cervicalis has two roots - a superior root and an inferior root - that unite distally, forming a loop. It is situated within the carotid sheath.

<span class="mw-page-title-main">Sternohyoid muscle</span>

The sternohyoid muscle is a bilaterally paired, long, thin, narrow strap muscle of the anterior neck. It is one of the infrahyoid muscles. It is innervated by the ansa cervicalis. It acts to depress the hyoid bone.

<span class="mw-page-title-main">Thyrohyoid muscle</span> Neck muscle that depresses the hyoid bone and elevates the larynx

The thyrohyoid muscle is a small skeletal muscle of the neck. Above, it attaches onto the greater cornu of the hyoid bone; below, it attaches onto the oblique line of the thyroid cartilage. It is innervated by fibres derived from the cervical spinal nerve 1 that run with the hypoglossal nerve to reach this muscle. The thyrohyoid muscle depresses the hyoid bone and elevates the larynx during swallowing. By controlling the position and shape of the larynx, it aids in making sound.

<span class="mw-page-title-main">Palatoglossus muscle</span> Muscle of the soft palate

The palatoglossal muscle is a muscle of the soft palate and an extrinsic muscle of the tongue. Its surface is covered by oral mucosa and forms the visible palatoglossal arch.

<span class="mw-page-title-main">Carotid sheath</span>

The carotid sheath is a condensation of the deep cervical fascia enveloping multiple vital neurovascular structures of the neck, including the common and internal carotid arteries, the internal jugular vein, the vagus nerve, and ansa cervicalis. The carotid sheath helps protects the structures contained therein.

<span class="mw-page-title-main">Anterior triangle of the neck</span>

The anterior triangle is a region of the neck.

<span class="mw-page-title-main">Subclavian nerve</span>

The subclavian nerve, also known as the nerve to the subclavius, is small branch of the upper trunk of the brachial plexus. It contains axons from C5 and C6. It innervates the subclavius muscle.

<span class="mw-page-title-main">Carotid triangle</span>

The carotid triangle is a portion of the anterior triangle of the neck.

<span class="mw-page-title-main">Muscular triangle</span>

The inferior carotid triangle, is bounded, in front, by the median line of the neck from the hyoid bone to the sternum; behind, by the anterior margin of the sternocleidomastoid; above, by the superior belly of the omohyoid.

<span class="mw-page-title-main">Cervical spinal nerve 1</span> Spinal nerve of the cervical segment

The cervical spinal nerve 1 (C1) is a spinal nerve of the cervical segment. C1 carries predominantly motor fibres, but also a small meningeal branch that supplies sensation to parts of the dura around the foramen magnum.

<span class="mw-page-title-main">Thyrohyoid branch</span> Nervous system structure

The thyrohyoid branch (also: thyrohyoid branch of ansa cervicalis, or nerve to thyrohyoid (muscle)) is a motor branch derived from the cervical plexus formed by fibres of (the anterior ramus of) the cervical spinal nerve 1 (C1) (and - according to some sources - cervical spinal nerve 2 (C2) as well) that join and travel with the hypoglossal nerve (cranial nerve XII) to reach the suprahyoid region, branching away from CN XII distal to the superior root of ansa cervicalis (which is a branching other fibres of C1-C2 that had traveled with the CN XII), near the posterior border of the hyoglossus muscle. The thyrohyoid branch of ansa cervicalis innervates the thyrohyoid muscle.

References

PD-icon.svgThis article incorporates text in the public domain from page 393 of the 20th edition of Gray's Anatomy (1918)

  1. "Genio-". Merriam-Webster Dictionary. Chin
  2. 1 2 3 Singh I (2009). Essentials of anatomy (2nd ed.). New Delhi: Jaypee Bros. p. 346. ISBN   978-81-8448-461-8.
  3. 1 2 Drake RL, Vogel W, Mitchell AW (2020). "Head and Neck". Gray's Anatomy for Students (Fourth ed.). Philadelphia, PA. pp. 823–1121. ISBN   978-0-323-39304-1.{{cite book}}: CS1 maint: location missing publisher (link)
  4. 1 2 Takahashi S, Ono T, Ishiwata Y, Kuroda T (December 2002). "Breathing modes, body positions, and suprahyoid muscle activity". Journal of Orthodontics. 29 (4): 307–13, discussion 279. CiteSeerX   10.1.1.514.2998 . doi:10.1093/ortho/29.4.307. PMID   12444272.
  5. Drake RL, Vogl W, Mitchell AW, Gray H (2005). Gray's anatomy for students (Pbk. ed.). Philadelphia: Elsevier/Churchill Livingstone. p. 988. ISBN   978-0-443-06612-2.
  6. Barney A, Martelli S, Serrurier A, Steele J (January 2012). "Articulatory capacity of Neanderthals, a very recent and human-like fossil hominin". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences. 367 (1585): 88–102. doi:10.1098/rstb.2011.0259. PMC   3223793 . PMID   22106429.